ADT: Admit, Discharge, Transfer

ADT carries patient administration events: a patient arriving, moving between wards, being discharged, or having their demographics corrected. It is the busiest interface in most hospitals, because almost every other system needs to know who the patient is and where they are.

Recognising ADT messages

ADT announces itself in MSH-9 like this:

How to use these specifications explains MSH-9 in full, with a worked example.

Here it is in a real message. Look at the first line.

MSH|^~\&|EPIC|STJOSEPH|LABSYS|STJOSEPH|20240314093015||ADT^A01^ADT_A01|MSG00017|P|2.5.1
EVN||20240314093000
PID|1||1000345678^^^STJOSEPH^MR~453-22-9911^^^USA^SS||CARTWRIGHT^ELEANOR^MAY^^^^L||19510822|F||2106-3|41 ORCHARD LANE^APT 2B^PORTLAND^OR^97202^USA^H||^PRN^PH^^1^503^5550142|^WPN^PH^^1^503^5550188|eng|M|CHR|100034567800
PV1|1|I|3W^312^A^STJOSEPH||||1447312^OKONKWO^ADAEZE^^^^MD|||MED||||1|||1447312^OKONKWO^ADAEZE^^^^MD|I|V100034567|SELF|||||||||||||||||||SJ||A|||20240314093000

Message structures

ADT takes 25 structures. The first 4 are shown in full; the rest are listed below.

ADT_A01: Admit/Visit Notification

4 different trigger events send this structure:

• A01Admit/Visit Notification
• A04Register a Patient
• A08Update Patient Information
• A13Cancel Discharge / End Visit

You must always send: MSH, EVN, PID, PV1. Everything else is optional, or required only inside a group you chose to send.

R inside a group means required of that group. Send the group and you must include that segment; leave the group out and it never appears. This structure has 2 such groups: PROCEDURE, INSURANCE.

ADT_A02: Transfer a Patient

Sent when one thing happens: A02: Transfer a Patient.

ADT_A03: Discharge/End Visit

Sent when one thing happens: A03: Discharge/End Visit.

ADT_A05: Pre-Admit a Patient

4 different trigger events send this structure:

• A05Pre-Admit a Patient
• A14Pending Admit
• A28Add Person or Patient Information
• A31Update Person Information

Other ADT structures

Trigger events

The trigger event is the real-world thing that made the message get sent. ADT defines 57.

Related

• MSHthe header carrying MSH-9, where the type and event are declared
• All message typesthe complete list